Sample preparation in which the sample is allowed to settle by leaving it undisturbed in a vessel.

• A. Centrifugation
• B. Sedimentation
• C. Filtration
• D. Decantation

Answer: (B)

Sedimentation is the gravity-driven separation of solids from a liquid when a suspension is left undisturbed. Heavier particles settle to the bottom, forming a sediment, while the clearer liquid remains above. Centrifugation speeds this up with spinning; filtration uses a filter to trap solids; decantation is pouring off the liquid after settling has occurred. So, the described scenario matches sedimentation.